Debt Instrument, Cross Default Provision, Maximum Term if Acceleration is not Rescinded

No definition available.

Name:	lii_DebtInstrumentCrossDefaultProvisionMaximumTermifAccelerationisnotRescinded
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- Definition

Minimum amount of principal or interest due on indebtedness or receivable securitization.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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Lines of Credit and Financing Arrangements (Senior Unsecured Notes) (Details) - Senior Unsecured Notes [Member] - USD ($)	12 Months Ended
	Dec. 31, 2021	Jul. 30, 2017	Nov. 01, 2016
Debt Instrument [Line Items]
Fixed interest rate for senior unsecured notes			3.00%
Minimum amount of principal or interest due on indebtedness or receivable securitization	$ 75,000,000
Number of days within notice date acceleration is not rescinded	30 days
2025 Notes [Member]
Debt Instrument [Line Items]
Debt issued		$ 300
Fixed interest rate for senior unsecured notes		1.35%
2027 Notes [Member]
Debt Instrument [Line Items]
Fixed interest rate for senior unsecured notes		1.70%
2023 Notes [Member]
Debt Instrument [Line Items]
Debt issued			$ 350,000,000